Coating providing modulated release of volatile compositions

ABSTRACT

Described are modulating coatings that are configured to provide an improved release profile of a volatile composition from a base material, wherein the modulating coating includes a barrier substance that is configured to hinder a release of the volatile composition through the modulating coating, and a hygroscopic substance that is configured to facilitate the release of the volatile composition through the modulating coating.

FIELD OF THE INVENTION

The field of the invention relates to articles that provide modulatedrelease of volatile compositions, and more specifically relate toarticles that provide a modulated release of volatile olfactory orfragrance compounds.

BACKGROUND

Fragrance-releasing devices are well known and commonly used inhousehold and commercial establishments to provide a pleasantenvironment for people in the immediate space. Further, aroma-drivenexperiences are well recognized to improve or enhance the general moodof individuals. In some instances, fragrances may trigger memories ofexperiences associated with the specific scent. Whether it is providinga pleasant environment, affecting a general demeanor, or triggering anostalgic memory, a steady, long-lasting release of fragrance willensure consumer and customer satisfaction.

Fragrance-release devices based on passive diffusion are limited intheir product-use by a finite supply of the fragrance and itsevaporation rate from a surface. In some examples, the fragrance-releasedevice is designed to carry the fragrance liquid within its architectureso that the fragrance supply is finite and determined by the size of thefragrance-release device.

The evaporation rate of fragrance from the fragrance-release device isdetermined, at least in part, by the composition of the fragrance, wherecompositions containing more volatile compounds (e.g. “top” notes) willevaporate faster than those with less volatile compounds (e.g. “base”notes). A fragrance composition determines its character. As a result,changing the composition of the fragrance will affect the character. Therelease rate profile of fragrance is generally strong (more intense) atthe beginning of product use, followed by decreasing intensity overtime. In some instances, the release rate exhibits a steep slope (as canbe seen in the plot of fragrance release over time in FIG. 5 and thecumulative fragrance loss over time in FIG. 6), where the initialfragrance release is too strong and the fragrance release time is tooshort. For these fragrances, there is a need to modulate the release offragrance from the fragrance-release device to provide a steady andlong-lasting fragrance release without changing the fragrance load andcharacter. Specifically there is a need to temper the release offragrance compounds at the initial stage of product use, followed byfacilitation of fragrance compound release at the later stage of productuse.

SUMMARY

The terms “invention,” “the invention,” “this invention” and “thepresent invention” used in this patent are intended to refer broadly toall of the subject matter of this patent and the patent claims below.Statements containing these terms should be understood not to limit thesubject matter described herein or to limit the meaning or scope of thepatent claims below. Embodiments of the invention covered by this patentare defined by the claims below, not this summary. This summary is ahigh-level overview of various aspects of the invention and introducessome of the concepts that are further described in the DetailedDescription section below. This summary is not intended to identify keyor essential features of the claimed subject matter, nor is it intendedto be used in isolation to determine the scope of the claimed subjectmatter. The subject matter should be understood by reference toappropriate portions of the entire specification of this patent, any orall drawings and each claim.

According to certain embodiments of the present invention, a modulatingcoating is configured to provide an improved release profile of avolatile composition from a base material, wherein the modulatingcoating comprises a barrier substance that is configured to hinder arelease of the volatile composition through the modulating coating, anda hygroscopic substance that is configured to facilitate the release ofthe volatile composition through the modulating coating.

In some embodiments, the hygroscopic substance is configured tofacilitate the release of the volatile composition through themodulating coating by attracting water molecules into the modulatingcoating to displace the volatile composition trapped by the barriersubstance within the modulating coating.

In certain embodiments, the hygroscopic substance comprises silica. Inthese embodiments, the barrier substance may comprise maltodextrin.

According to some embodiments, the weight ratio of the barrier substanceto the hygroscopic substance ranges from 99:1 to 1:99. The weight ratioof the barrier substance to the hygroscopic substance may further rangefrom 25:75 to 75:25. The weight ratio of the barrier substance to thehygroscopic substance may also be approximately 50:50.

In certain embodiments, the particle size of the hygroscopic substanceranges from 0.001 μm-1 μm.

According to certain embodiments of the present invention, an articlecomprises a base material comprising an internal structure, a volatilecomposition, wherein at least some of the volatile composition islocated in the internal structure, and a modulating coating at leastpartially located on at least one outer surface of the base material,wherein the modulating coating comprises a barrier substance and ahygroscopic substance.

In certain embodiments, the hygroscopic substance comprises silica. Inthese embodiments, the barrier substance may comprise maltodextrin.

According to some embodiments, the weight ratio of the barrier substanceto the hygroscopic substance ranges from 99:1 to 1:99. The weight ratioof the barrier substance to the hygroscopic substance may further rangefrom 25:75 to 75:25. The weight ratio of the barrier substance to thehygroscopic substance may also be approximately 50:50.

In certain embodiments, the particle size of the hygroscopic substanceranges from 0.001 μm-1 μm.

According to some embodiments, the base material may comprise a pulpcomposition.

In certain embodiments, at least some of the volatile composition islocated within the modulating coating, wherein the modulating coatingfurther comprises water that is absorbed or adsorbed to the hygroscopicsubstance.

According to certain embodiments of the present invention, an articlecomprises a base material comprising an internal structure comprisingpores, a volatile composition, wherein at least some of the volatilecomposition is located in the pores, and a modulating coating at leastpartially located on at least one outer surface of the base material,wherein the article exhibits a ratio of a first day weight-loss value toa last day weight-loss value in a range of 1 to 20 over a 30 day lifecycle of the article.

According to certain embodiments of the present invention, a method ofcoating a base material comprises applying a modulating coating to atleast one outer surface of the base material, wherein the modulatingcoating comprises a barrier substance that hinders a release of avolatile composition through the modulating coating, and a hygroscopicsubstance that facilitates the release of the volatile compositionthrough the modulating coating.

In certain embodiments, the modulating coating is applied to the atleast one outer surface of the base material by at least one of gravureprinting, offset printing, or flexographic printing. The modulatingcoating may also be applied to the at least one outer surface of thebase material by at least one of a dip method, an infusion method, orspray treatment.

In certain embodiments, the method further comprises winding the basematerial into a spiral wound roll. The method may also further compriseconverting the base material into an article having a three-dimensionalstructure.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed description, embodiments of the invention aredescribed referring to the following figures:

FIG. 1 is a schematic illustrating the movement of a volatilecomposition across an internal structure of a base material and amodulating coating over time, according to certain embodiments of thepresent invention.

FIG. 2 is a cross-sectional view of an article formed from a basematerial and coated with a modulating coating, according to certainembodiments of the present invention. The triangle schematic representsa concentration gradient of modulating coating 14 based on depth ofpenetration.

FIG. 3 is another cross-sectional view and a partial close-up view ofthe article of FIG. 2.

FIG. 4 is a view of an outer surface of articles formed from a basematerial with the article on the left coated with the modulating coatingand the article on the right uncoated, according to certain embodimentsof the present invention.

FIG. 5 is a graph showing the release rate in grams per day of avolatile composition loaded in an uncoated article.

FIG. 6 is a graph showing the cumulative amount released over time of avolatile composition loaded in an uncoated article.

FIG. 7 is a graph showing the release rate in grams per day of avolatile composition loaded in an uncoated article and loaded inarticles coated with modulating coatings using different ratios ofbarrier substances and hygroscopic substances.

FIG. 8 is a graph showing the cumulative amount released over time of avolatile composition loaded in an uncoated article and loaded inarticles coated with modulating coatings using different ratios ofbarrier substances and hygroscopic substances.

FIG. 9 is a graph showing the release rate in grams per day of aconcentrated volatile composition loaded in an article coated with amodulating coating and loaded in an uncoated article, as well as therelease rate in grams per day of a standard concentration of a volatilecomposition loaded in an article coated with a modulating coating andloaded in an uncoated article.

FIG. 10 is a graph showing the cumulative amount released over time of aconcentrated volatile composition loaded in an article coated with amodulating coating and loaded in an uncoated article.

FIG. 11 is a graph showing the release rate in grams per day of aconcentrated volatile composition loaded in an article coated with amodulating coating and loaded in an uncoated article.

FIG. 12 is a graph showing the cumulative amount released over time of aconcentrated volatile composition loaded in an article coated with amodulating coating and loaded in an uncoated article.

DETAILED DESCRIPTION

The subject matter of embodiments of the present invention is describedhere with specificity to meet statutory requirements, but thisdescription is not necessarily intended to limit the scope of theclaims. The claimed subject matter may be embodied in other ways, mayinclude different elements or steps, and may be used in conjunction withother existing or future technologies. This description should not beinterpreted as implying any particular order or arrangement among orbetween various steps or elements except when the order of individualsteps or arrangement of elements is explicitly described.

According to certain embodiments of the present invention, an article 10comprises a base material 12 and a modulating coating 14. The basematerial 12 may comprise an internal structure 20 comprising a pluralityof pores 22 that are configured to provide locations for the volatilecomposition 24 to be stored therein and released therefrom, which isdescribed in detail below.

As used herein, “coating” refers to any composition that can be appliedusing any suitable method to at least one of an outer surface of athree-dimensional article 10, to some or all surfaces of a base material12, and/or may be uniformly or non-uniformly mixed throughout theinternal structure 20 of the base material 12 and/or the article 10. Incases of surface application, the coating may be applied so that thecomposition may or may not penetrate to at least some degree within thearticle 10 and/or the base material 12.

The base material 12 may comprise natural and/or synthetic pulpcompositions; pulp compositions combined with other products, includingbut not limited to paper, cellulose, cellulose acetate, pulp lap, cottonlinters, biological plant-derived materials (from living plants),synthesized pulp compositions, and mixed pulps; polymer material; porousmaterial; and/or extrudate.

As known in the art, pulp is primarily a collection of fibers with othercomponents of the source material, wherein the fibers are derived from anatural or synthetic source material, for example, biological plants(natural) or petroleum-based synthesis products (synthetic). Pulp may beproduced from various types of woods using any one of several knownpulping techniques. The pulp may be from hardwoods, softwoods, ormixtures thereof. The pulp may also be made from recycled materials, andcomprises recovering waste paper and remaking it into new products.

In certain embodiments, the number and/or size of the plurality of pores22 (i.e., porosity) within the base material 12 may be controlled by thecompactness and/or size of the fibers and/or particles that form theinternal structure 20. For example, in certain embodiments of the basematerial 12 that comprise fibers, voids between the fibers form tiny airpassages throughout the internal structure 20. The compactness of thefibers affects the degree in which the base material 12 allows gas orliquid to pass through it. For example, porosity may affect uptake orload amount of volatile compositions, or may affect the rate of releaseof such substances. Porosity of the base material 12 may be affected byadding other materials, such as additives to the matrix material 12 asit is being formed from a composition, such as pulp or any othercomposition described above, so that the additives are located withinthe internal structure 20 of the base material 12 after formation.

The porosity of a base material 12 that comprises pulp may be affectedat any stage of the pulp production process. An increased level of fiberrefining causes the fibers to bond together more strongly and tightly,making the pulp material denser, thereby reducing the network of airpassages and the porosity. Surface sizing, coating, calendering orsupercalendering may also seal and/or further compress surface fibers.

The porosity of the base material 12 is measured quantitatively aseither the length of time it takes for a quantity of air to pass througha sample, or the rate of the passage of air through a sample, usingeither a Gurley densometer (in the first case) or a Sheffieldporosimeter (in the second case). With the Gurley densometer, theporosity is measured as the number of seconds required for 100 cubiccentimeters of air to pass through 1.0 square inch of a given materialat a pressure differential of 4.88 inches of water, as described in ISO5646-5, TAPPI T-460, or TAPPI T-536.

The porosity may affect how completely and how quickly the volatilecomposition 24 is absorbed into a pulp base material 12, as suchabsorption may occur primarily by capillary action. For example, a pulpbase material 12 with high porosity may have increased absorbency of thevolatile composition 24. The porosity of the pulp base material 12 mayrange from 0.01 Gurley second-100 Gurley seconds, and all rangestherein. In certain embodiments where there are multiple layers of pulpbase material 12, the porosity may range from 0.01 Gurley second-20Gurley seconds. The volatile composition 24 may be applied to the basematerial 12 in the form of a film, or a coating, or a treatmentintegrated into the internal structure 20 of the base material 12.

The volatile composition 24 may include but is not limited tofragrances, flavor compounds, odor-eliminating compounds, aromatherapycompounds, natural oils, water-based scents, odor neutralizingcompounds, and outdoor products (e.g., insect repellent).

As used herein, “volatile substance” refers to any compound, mixture, orsuspension of compounds that are odorous, or compound, mixture, orsuspension of compounds that cancel or neutralize odorous compounds,such as any compound or combination of compounds that would produce apositive or negative olfactory sense response in a living being that iscapable of responding to olfactory compounds, or that reduces oreliminates such olfactory responses.

A volatile composition as used herein comprises one or more volatilesubstances and is generally a composition that has a smell or odor,which may be volatile, which may be transported to the olfactory systemof a human or animal, and is generally provided in a sufficiently highconcentration so that it will interact with one or more olfactoryreceptors.

A fragrance may comprise an aroma or odorous compound, mixture orsuspension of compounds that is capable of producing an olfactoryresponse in a living being capable of responding to olfactory compounds,and may be referred to herein as odorant, aroma, or fragrance. Afragrance composition may include one or more than one of the fragrancecharacteristics, including top notes, mid notes or heart, and the drydown or base notes. The volatile composition 24 may comprise otherdiluents or additives, such as solvents or preservatives.

Examples of volatile compositions 24 useful in the present inventioninclude but are not limited to, esters, terpenes, cyclic terpenes,phenolics which are also referred to as aromatics, amines and alcohols.For example, furaneol 1-hexanol, cis-3-Hexen-1-ol, menthol,acetaldehyde, hexanal, cis-3-hexenal, furfural, fructone, hexyl acetate,ethyl methylphenylglycidate, dihydrojasmone, wine lactone,oct-1-en-3-one, 2-Acetyl-1-pyrroline,6-acetyl-2,3,4,5-tetrahydropyridine, gamma-decalactone,gamma-nonalactone, delta-octalactone, jasmine, massoia lactone, sotolonethanethiol, grapefruit mercaptan, methanethiol,2-methyl-2-propanethiol, methylphosphine, dimethylphosphine, methylformate, nerolin tetrahydrothiophene, 2,4,6-trichloroanisole,substituted pyrazines, methyl acetate, methyl butyrate, methylbutanoate, ethyl acetate, ethyl butyrate, ethyl butanoate, isoamylacetate, pentyl butyrate, pentyl butanoate, pentyl pentanoate, isoamylacetate, octyl acetate, myrcene, geraniol, nerol, citral, lemonal,geranial, neral, citronellal, citronellol, linalool, nerolidol,limonene, camphor, terpineol, alpha-ionone, terpineol, thujone,benzaldehyde, eugenol, cinnamaldehyde, ethyl maltol, vanillin, anisole,anethole, estragole, thymoltrimethylamine, putrescine, diaminobutane,cadaverine, pyridine, indole and skatole. Most of these are organiccompounds and are readily soluble in organic solvents, such as alcoholsor oils. Fragrance includes pure fragrances such as those includingessential oils and are known to those skilled in the art. Water-basedodorous compounds and other odorous compositions are also contemplatedby the present invention.

Fragrance oils as olfactory-active compounds or compositions usuallycomprise many different perfume raw materials. Each perfume raw materialused differs from another by several important properties includingindividual character and volatility. By bearing in mind these differentproperties, and others, the perfume raw material can be blended todevelop a fragrance oil with an overall specific character profile. Todate, characters are designed to alter and develop with time as thedifferent perfume raw materials evaporate from the substrate and aredetected by the user. For example, perfume raw materials which have ahigh volatility and low substantivity are commonly used to give aninitial burst of characters such as light, fresh, fruity, citrus, greenor delicate floral to the fragrance oil which are detected soon afterapplication. Such materials are commonly referred to in the field offragrances as “top notes.” By way of a contrast, the less volatile, andmore substantive, perfume raw materials are typically used to givecharacters such as musk, sweet, balsamic, spicy, woody or heavy floralto the fragrance oil which, although may also be detected soon afterapplication, also last far longer. These materials are commonly referredto as “middle notes” or “base notes.” Highly skilled perfumers areusually employed to carefully blend perfume raw materials so that theresultant fragrance oils have the desired overall fragrance characterprofile. The desired overall character is dependent both upon the typeof composition in which the fragrance oil will finally be used and alsothe consumer preference for a fragrance.

In addition to the volatility, another important characteristic of aperfume raw material is its olfactory detection level, otherwise knownas the odor detection threshold (ODT). If a perfume raw material has alow odor detection threshold, only very low levels are required in thegas phase, or air, for it to be detected by the human, sometimes as lowas a few parts per billion. Conversely, if a perfume raw material has ahigh ODT, larger amounts or higher concentrations in the air of thatmaterial are required before it can be smelled by the user. The impactof a material is its function of its gas phase or air concentration andits ODT. Thus, volatile materials, capable of delivering large gas-phaseconcentrations, which also have low ODTs, are considered to beimpactful. To date, when developing a fragrance oil, it has beenimportant to balance the fragrance with both low and high volatility rawmaterials since the use of too many high volatility materials could leadto a short lived, overwhelming scent. As such the levels of high odorimpact perfume raw materials within a fragrance oil have traditionallybeen restricted.

As used herein the term “fragrance oil” relates to a perfume rawmaterial, or mixture of perfume raw materials, that are used to impartan overall pleasant odor profile to a composition, preferably a cosmeticcomposition. As used herein the term “perfume raw material” relates toany chemical compound which is odorous when in an un-entrapped state,for example in the case of pro-perfumes, the perfume component isconsidered to be a perfume raw material, and the pro-chemistry anchor isconsidered to be the entrapment material. In addition “perfume rawmaterials” are defined by materials with a ClogP value preferablygreater than about 0.1, more preferably greater than about 0.5, evenmore preferably greater than about 1.0. As used herein the term “ClogP”means the logarithm to base 10 of the octanol/water partitioncoefficient. This can be readily calculated from a program called“CLOGP,” which is available from Daylight Chemical Information SystemsInc., Irvine Calif., USA. Octanol/water partition coefficients aredescribed in more detail in U.S. Pat. No. 5,578,563.

Examples of residual “middle and base note” perfume raw materialsinclude, but are not limited to, ethyl methyl phenyl glycidate, ethylvanillin, heliotropin, indol, methyl anthranilate, vanillin, amylsalicylate, coumarin. Further examples of residual perfume raw materialsinclude, but are not limited to, ambrox, bacdanol, benzyl salicylate,butyl anthranilate, cetalox, ebanol, cis-3-hexenyl salicylate, lilial,gamma undecalactone, gamma dodecalactone, gamma decalactone, calone,cymal, dihydro iso jasmonate, iso eugenol, lyral, methyl beta naphthylketone, beta naphthol methyl ether, para hydroxylphenyl butanone,8-cyclohexadecen-1-one, oxocyclohexadecen-2-one/habanolide, florhydral,intreleven aldehyde.

Examples of volatile “top note” perfume raw materials include, but arenot limited to, anethol, methyl heptine carbonate, ethyl aceto acetate,para cymene, nerol, decyl aldehyde, para cresol, methyl phenyl carbinylacetate, ionone alpha, ionone beta, undecylenic aldehyde, undecylaldehyde, 2,6-nonadienal, nonyl aldehyde, octyl aldehyde. Furtherexamples of volatile perfume raw materials include, but are not limitedto, phenyl acetaldehyde, anisic aldehyde, benzyl acetone, ethyl-2-methylbutyrate, damascenone, damascone alpha, damascone beta, flor acetate,frutene, fructone, herbavert, iso cyclo citral, methyl isobutenyltetrahydro pyran, isopropyl quinoline, 2,6-nonadien-1-ol,2-methoxy-3-(2-methylpropyl)-pyrazine, methyl octine carbonate,tridecene-2-nitrile, allyl amyl glycolate, cyclogalbanate, cyclal C,melonal, gamma nonalactone, c is 1,3-oxathiane-2-methyl-4-propyl.

Other useful residual “middle and base note” perfume raw materialsinclude, but are not limited to, eugenol, amyl cinnamic aldehyde, hexylcinnamic aldehyde, hexyl salicylate, methyl dihydro jasmonate,sandalore, veloutone, undecavertol, exaltolide/cyclopentadecanolide,zingerone, methyl cedrylone, sandela, dimethyl benzyl carbinyl butyrate,dimethyl benzyl carbinyl isobutyrate, triethyl citrate, cashmeran,phenoxy ethyl isobutyrate, iso eugenol acetate, helional, iso E super,ionone gamma methyl, pentalide, galaxolide, phenoxy ethyl propionate.

Other volatile “top note” perfume raw materials include, but are notlimited to, benzaldehyde, benzyl acetate, camphor, carvone, borneol,bornyl acetate, decyl alcohol, eucalyptol, linalool, hexyl acetate,iso-amyl acetate, thymol, carvacrol, limonene, menthol, iso-amylalcohol, phenyl ethyl alcohol, alpha pinene, alpha terpineol,citronellol, alpha thuj one, benzyl alcohol, beta gamma hexenol,dimethyl benzyl carbinol, phenyl ethyl dimethyl carbinol, adoxal, allylcyclohexane propionate, beta pinene, citral, citronellyl acetate,citronellal nitrile, dihydro myrcenol, geraniol, geranyl acetate,geranyl nitrile, hydroquinone dimethyl ether, hydroxycitronellal,linalyl acetate, phenyl acetaldehyde dimethyl acetal, phenyl propylalcohol, prenyl acetate, triplal, tetrahydrolinalool, verdox,cis-3-hexenyl acetate.

In certain embodiments, the volatile composition 24 may comprise afragrance component having a release rate ranging from 0.001 g/day to2.0 g/day. The formulation of the fragrance may comprise any suitablecombination of top, mid, and base note components.

The modulating coating 14 may be applied to at least one outer surface16 of the base material 12 and/or to the article 10, and may be appliedbefore or after loading of the volatile composition 24. In certainembodiments, as best illustrated in FIGS. 2-3, the modulating coating 14may penetrate into the internal structure 20 of the base material 12 toa certain level, which may vary depending on the porosity, processingmethods, or other characteristics of the base material 12.

The modulating coating 14 is designed to slow the release rate of thevolatile composition 24 loaded into the internal structure 20 at higherconcentration levels and accelerate the release rate of the volatilecomposition 24 at lower concentration levels in order to achieve arelatively steady release of volatile composition 24 over time, asillustrated in FIGS. 7-8 and 11-12.

To explain the way that the modulating coating 14 works to have this“hold/push” effect over a range of load levels of the volatilecomposition 24, it is necessary to explain the way in which the releaserate of the volatile composition 24 is generated. The volatilecomposition 24 is loaded or absorbed into the internal structure 20 viathe pores 22 until a sufficiently high load level is achieved within theinternal structure 20 through various embodiments of loading methods,which are explained in detail below. The volatile composition 24 may beloaded or absorbed into the internal structure 20 before or after themodulating coating 14 is applied.

The initially high load level of the volatile composition 24 within theinternal structure 20 creates an internal force that causes the volatilecomposition 24 to diffuse or evaporate out of the internal structure 20as quickly as possible to a region of lower concentration. As the loadlevel of the volatile composition 24 decreases over time, the force thatcauses the diffusion or evaporation diminishes until there is no longera force remaining (i.e., an equilibrium point is reached where thevolatile composition 24 no longer diffuses or evaporates out of theinternal structure 20). The equilibrium point is usually higher than 0%concentration, which causes some of the volatile composition 24 tobecome trapped within the pores 22 of the internal structure 20.

In conventional applications, such as in U.S. Publication No.20110262377, a coating may be applied to form a layer that slows orretards the rapid release of a volatile composition at higherconcentration levels. These conventional coatings typically includesubstances that trap some of the volatile composition within the coatinglayer, which slows down the rate of release through the coating.However, because the coating only serves as a barrier or “speed bump” toslow down the rate of release of the volatile composition, the releasewill eventually stop once the concentration of volatile compositionwithin the internal structure reaches equilibrium (i.e., a level wherethere is no longer a sufficient concentration to drive the volatilecomposition through the coating layer, thus allowing some of volatilecomposition to remain trapped within the coating layer and/or within theinternal structure).

The modulating coating 14 comprises both a barrier substance 26 and ahygroscopic substance 28. In particular, in most embodiments, themodulating coating 14 comprises substances that do not chemicallyinteract with the volatile composition 24 itself.

In these embodiments, when the modulating coating 14 is applied to theouter surface 16 of the internal structure 20, at the higherconcentration levels of the volatile composition 24 within the internalstructure 20, the barrier substance 26 forms a barrier or “speed bump”to slow down the rate of release of the volatile composition 24 throughthe modulating coating 14. At these higher initial concentration levels,as illustrated in the early stage section of FIG. 1, the hygroscopicsubstance 28 does not play a role in modulating the release rate of thevolatile composition 24 (i.e., does not absorb any water into themodulating coating 14) because the concentration of the volatilecomposition 24 within the internal structure 20 is sufficiently high toforce a certain amount of the volatile composition 24 to release throughthe modulating coating 14 at a rate that effectively blocks any waterfrom being attracted into the modulating coating 14 by the hygroscopicsubstance 28.

As the concentration level of the volatile composition 24 within theinternal structure 20 slowly diminishes, as illustrated in the mid stagesection of FIG. 1, the concentration of the volatile composition 24within the internal structure 20 is still sufficiently high to continueto force some of the volatile composition 24 out of the modulatingcoating 14 at a reduced rate of release.

One hypothesis to explain the phenomenon observed in the late stage, assuggested in the graphs of release rate over time in FIGS. 7-8 and11-12, is that because there is a lower volume of the volatilecomposition 24 exiting the modulating coating 14, the hygroscopicsubstance 28 begins to attract more water (typically in the form ofwater vapor) into the modulating coating 14, whereupon the water adsorbsor absorbs to the hygroscopic substance 28 and begins to displace thevolatile composition 24 that is trapped by the barrier substance 26within the modulating coating 14. This hypothesis is illustrated in thelate stage section of FIG. 1, and is based on known physical propertiesof the hygroscopic substance 28 and the data showing higher releaserates at the end of the product life cycle, as compared to the sameproduct without the modulating coating 14. Once displaced, the volatilecomposition 24 is released from the modulating coating 14, therebycreating an aggregate rate of release of the volatile composition 24that may approximate the rate of release driven by the higher load levelof the volatile composition 24 alone.

As the load level of volatile composition 24 continues to drop to alevel that can no longer drive the volatile composition 24 out of themodulating coating 14, the hygroscopic substance 28 continues to pullmore and more water into the modulating coating 14. That water continuesto displace the trapped volatile composition 24, effectively forcing thedisplaced volatile composition 24 to be released from the modulatingcoating 14. For a period of time in the late stage, as illustrated inFIGS. 7-8 and 11-12, the rate of release of the volatile composition 24due to water displacement driven by the hygroscopic substance 28 mayapproximate the rate of release driven by the higher load level of thevolatile composition 24 alone and/or may approximate the aggregate rateof release driven by both the higher load level of the volatilecomposition 24 and water displacement driven by the hygroscopicsubstance 28. As a result, where conventional coatings that contain onlybarrier substances 26 may have stopped releasing volatile compositionsonce the equilibrium point of the concentration is reached within theinternal structure 20, the modulating coating 14 continues to provide arelatively constant release of the volatile composition 24.

An alternate hypothesis to explain the phenomenon observed in the latestage as seen in FIGS. 7-8 and 11-12 is that the water that is broughtinto the modulating coating 14 by the hygroscopic substance 28 may actto degrade the barrier substance 26, which would also allow for releaseof the volatile composition 24 trapped within the modulating coating 14and within the internal structure 20 of the base material 12.

In any event, the test results demonstrate that the modulating coating14 generates an improved release profile of the volatile composition 24over the aromatic life cycle of the article 10, depending on theporosity of the internal structure 20 of the base material 12 and thevolatility levels of the volatile composition 24. Eventually, theconcentration of the volatile composition 24 within the internalstructure 20 and the amount trapped by the barrier substances 26 withinthe modulating coating 14 will reach such a low point that the amount ofvolatile composition 24 released on a daily basis by the modulatingcoating 14 will eventually decline to zero.

In certain embodiments, the barrier substance 26 may comprisemaltodextrin (e.g. Maltrin). In other embodiments, the barrier substance26 may include but is not limited to other dextrins, other film-formingpolysaccharides, other carbohydrates (mono-, di-, tri-, etc.), naturalunmodified starch, modified starch, any starch appropriate for use inpapermaking, as well as combinations of starch types, dextrin types, andcombinations of starches and dextrins. In certain embodiments, thebarrier substance 26 may include but not is limited to additives such asinsolubilizers, lubricants, dispersants, defoamers, crosslinkers,binders, surfactants, leveling agents, wetting agents, surfaceadditives, rheology modifiers, non-stick agents, and other coatingadditives.

In certain embodiments, the hygroscopic substance 28 may comprise silica(e.g. silica nanoparticles). In other embodiments, the hygroscopicsubstance 28 may include but is not limited to other hygroscopicreagents, activated charcoal, calcium sulfate, calcium chloride, andmolecular sieves, or other suitable water absorbing materials.

The weight ratio of the barrier substance 26 to the hygroscopicsubstance 28 may range from 99:1 to 1:99, and all ranges thereinbetween. In certain embodiments, weight ratio of the barrier substance26 to the hygroscopic substance 28 may further range from 25:75 to75:25. In yet other embodiments, the weight ratio of the barriersubstance 26 to the hygroscopic substance 28 may be approximately 50:50.

In certain embodiments, the particle size of the hygroscopic substance28 is determined in part by the amount of surface area needed to attractenough water to counteract the drop in release rate due to a reductionin the load level of the volatile composition 24. The hygroscopicsubstance 28 is also configured so that it will attract water vapor,rather than liquid water. As a result, the diameter of the particle sizeof the hygroscopic substance 28 may range from 0.001 μm-1 μm, and allranges therein between, and may further range from 1 nm-100 nm, whichwill attract the appropriate amount of water vapor molecules, as well asproviding a more even coating.

In certain embodiments, the hygroscopic substance 28 may have a surfacecharge range that ensures interaction with the barrier substances 26.For example, in the case of silica, the surface charge ranges from −10mV to −4000 mV, as measured by Zeta potential, which is a highly anionicpoint charge. When the silica is mixed with the maltodextrin beforecoating, the maltodextrin may group around the silica particles, whichmay further assist with the barrier formation within the modulatingcoating 14.

In certain embodiments, the modulating coating 14 may provide a moreconsistent release rate of the volatile compound 24. The consistency(variance) may be measured by the following formula.

Variance_((Weight-loss ratio))=First day weight-loss value/Last dayweight-loss value

The benefit of the modulating coating 14 is to reduce the variancewithin a ratio range of 1 to 20 over a life cycle of the article, whichin certain embodiments may be 30 days, but could be longer or shorter asneeded or desired. As exhibited in Example 6, FIG. 7, the reduction inVariance_((Weight-loss ratio)) for pulp base material 12 treated withmodulating coating 14 (i.e., the ratio range) is approximately 10.

Furthermore, as demonstrated in Example 7 and accompanying FIGS. 9-10,in certain embodiments, use of a more concentrated version of thevolatile composition 24 in combination with the modulating coating 14provides release rate improvement as disclosed herein and presentscommercial advantages over the use of the standard version of volatilecomposition 24 without modulating coating 14. The term “concentrated”used herein is intended to describe a higher amount of olfactory-activecompounds or compositions relative to other non-volatile substanceswithin the volatile composition 24. A more concentrated version of avolatile composition 24 will release into the atmosphere faster than itsstandard version, thus providing a higher than desired scent intensityand character. Application of modulating coating 14 will moderate thisfaster release, resulting in a new release rate that has the desiredintensity and character.

In certain embodiments, the loaded amount of a more concentrated versionof the volatile composition 24 into base material 12 coated withmodulating coating 14 may be less than the loaded amount of the standardversion of a volatile composition 24. This increased concentration, incombination with the optimal release rate, provides the opportunity foran increased duration of release and/or for material cost savings (byreducing the initial volatile composition load).

The base material 12 may be converted into the article 10, which mayoccur before or after the modulating coating 14 and/or the volatilecomposition 24 are applied.

In certain embodiments, the article 10 may comprise a singletwo-dimensional layer with varying shapes and thicknesses, such as flatsheet embodiments, wherein the modulating coating 14 may be applied toboth the outer surface 16 and an opposing surface 18 of the basematerial 12.

In other embodiments, the article 10 may comprise multipletwo-dimensional layers with varying shapes and thicknesses, wherein themodulating coating 14 may be applied to both the outer surface 16 ofeach layer of the base material 12 and arranged so that each uncoatedopposing surface 18 is mated with an adjacent coated outer surface 16 ofthe next layer.

In further embodiments, the article 10 may comprise a three-dimensionalstructure with varying shapes and sizes, such as a desired shape, asolid rod, a rod with a core, a rod with two cores, a rod with ahoneycomb structure, a solid sphere, a hollow sphere, or any othergeometric shape, or other possible arrangements.

In certain embodiments, the article 10 may comprise a spiral woundpaper. The spiral winding process allows for the paper to be the same ordifferent for each layer formed by winding the paper one completerevolution around the axis of the structural component. For example, astructural component may comprise a rod shape, formed by winding thebase material 12 (e.g., a paper matrix) around a vertical axis, so thata rod having a length longer than its diameter is formed. Each layerformed by the complete revolution of the paper matrix around the axismay be referred to as a ply. For example, a 10 ply rod may have from oneto ten different characteristics for each ply of the rod.Characteristics may include but are not limited to absorbance, tensilestrength density, pH, porosity, and polarity of the base material 12,and the type of paper or internal structure 20.

The modulating coating 14 may be applied to the base material 12 beforeor after application of the volatile composition 24. For example, themodulating coating 14 may be applied when the base material 12 is in atwo-dimensional form via conventional two-dimensional coating methodstypically used for treating two-dimensional sheets of material, such aspaper. These methods include but are not limited to at least one ofgravure printing, offset printing, flexographic printing, rod coating,blade coating, curtain coating, or other suitable coating methods. Inthese two-dimensional embodiments, the modulating coating 14 may beapplied to the base material 12 when the base material 12 is in a singletwo-dimensional layer, after which the base material 12 layers areassembled together to form the article 10. In other two-dimensionalembodiments, the base material 12 may be arranged into the layeredmaterial prior to application of the modulating coating 14 so that themodulating coating 14 is only applied to the outermost surface 16 of thetop layer of the base material 12 (although the modulating coating 14may penetrate to a certain depth within the article 10).

The modulating coating 14 may also be applied to the base material 12after it has been formed into the three-dimensional article 10. In theseembodiments, the modulating coating 14 may be applied to an outersurface of the article 10 (although the modulating coating 14 maypenetrate to a certain depth within the article 10, as illustrated inFIGS. 2-3).

For example, the modulating coating 14 may be applied to thethree-dimensional article 10 via a dip method where thethree-dimensional article 10 is placed within a volume of modulatingcoating 14 for a specified amount of time, then removed and allowed todry. The dip method may also be used with two-dimensional versions ofthe article 10. The add-on level may range from 0.1% to 10% by weight.Examples 2 and 3 describe specific non-limiting examples of diptreatment.

In other embodiments, the modulating coating 14 may be applied to thethree-dimensional article 10 via an infusion method with the add-oninfusion ranging from 1% to 20% by weight, and, in certain embodiments,may further range from 10% to 20% by weight. The infusion method mayalso be used with two-dimensional versions of the article 10. Example 4describes a specific non-limiting example of infusion treatment.

In yet other embodiments, the modulating coating 14 may be applied totwo-dimensional base material 12, two-dimensional articles 10 and/orthree-dimensional articles 10 via spray treatment.

The volatile composition 24 may be applied to the base material 12before or after application of the modulating coating 14, as describedabove. For example, the volatile composition 24 may be applied byplacing the base material 12 and/or the article 10 in intimate contactwith the volatile composition 24 for a period of time. The volatilecomposition 24 may be in any physical state, such as liquid, solid, gel,or gas. For convenience, a liquid volatile composition 24 is described,but this is not intended to be limiting. The interaction time may dependon the concentration or type of volatile composition 24 being applied tothe base material 12 and/or the article 10, and/or how strong or intenseof a volatile composition 24 release desired, and/or the type of basematerial 12. In certain embodiments, a rolled paper rod structuralcomponent with dimensions of 13.97 cm (length) and 0.64 cm (diameter)may be saturated with a liquid fragrance composition comprisingapproximately one (1) to three (3) grams of one or more pure fragrances,and the saturation time (interaction time) may range from less than oneminute to a several hours, to several days. The base material 12 and/orthe article 10 may be pre-treated prior to exposure to the volatilecomposition 24. For example, the base material 12 and/or the article 10may be placed in a drying oven to remove any residual moisture. Furthermethod steps comprise pressure treating and/or vacuum treating the basematerial 12 and/or the article 10. After treatment, the base material 12and/or the article 10 may be dried, for example by rubbing or pattingdry, and/or by other methods known for drying a surface, and/or may beleft to air dry. Drying steps may be used before or after other stepsdescribed herein.

In some embodiments, a method for applying the volatile composition 24to the base material 12 and/or to the article 10 comprises combining thevolatile composition 24 and the base material 12 and/or the article 10in a container and applying a pressure above atmospheric pressure on thevolatile composition 24 and base material 12 and/or the article 10.Pressure may be applied in a range from about 1 psi to about 40 psi,from about 5 psi to about 30 psi, or from about 10 psi to about 20 psi,at about 5 psi, at about 10 psi, at about 15 psi, at about 20 psi, atabout 25 psi, at about 30 psi, at about 35 psi, at about 40 psi, and/orat pressures therein between. The pressure may be applied for a periodof time from about 1 minute to about 10 hours, for about 30 minutes, forabout 1 hour, for about 2 hours, for about 3 hours, for about 4 hours,for about 5 hours for about 6 hours, for about 7 hours, for about 8hours, for about 9 hours, for about 10 hours, or longer if needed toapply sufficient amounts of the volatile composition 24 to the basematerial 12 and/or the article 10 to achieve a desired load of thevolatile composition 24 to the base material 12 and/or the article 10 orrelease of the volatile composition 24 from the base material 12 and/orthe article 10. Appropriate pressures and times for a particularembodiment can be determined by one skilled in the art based on theidentities and characteristics of the particular volatile composition 24and base material 12 and/or article 10.

In certain embodiments, a method for applying the volatile composition24 comprises combining the volatile composition 24 and base material 12and/or the article 10 in a container and applying a vacuum belowatmospheric pressure to the volatile composition 24 and the basematerial 12 and/or the article 10. Vacuum may be applied in a range from0.001 mm Hg to about 700 mm Hg, or from about 5 Kpa to about 35 kPa,from about 10 Kpa to about 25 kPa, from about 20 Kpa to about 30 kPa,from about 15 Kpa to about 25 kPa, from about 25 Kpa to about 30 kPa, atabout 5 kPa, at about 6 kPa, at about 7 kPa, at about 8 kPa, at about 9kPa, at about 10 kPa, at about 15 kPa, at about 16 kPa, at about 17 kPa,at about 18 kPa, at about 19 kPa, at about 20 kPa, at about 22 kPa, atabout 24 kPa, at about 26 kPa, at about 28 kPa, at about 30 kPa, andvacuums therein between. The vacuum may be applied for a period of timefrom about 1 minute to about 10 hours, for about 30 minutes, for about 1hour, for about 2 hours, for about 3 hours, for about 4 hours, for about5 hours for about 6 hours, for about 7 hours, for about 8 hours, forabout 9 hours, for about 10 hours, or longer if needed to applysufficient amounts of the volatile composition 24 to the base material12 and/or the article 10 to achieve a desired load of the volatilecomposition 24 to the base material 12 and/or the article 10 or releaseof the volatile composition 24 from the base material 12 and/or thearticle 10.

In yet other embodiments, the method may comprise pressure and vacuumsteps. The volatile composition 24 and the base material 12 and/or thearticle 10 may be combined and undergo vacuum treatment and pressuretreatment, in no particular order. For example, the volatile composition24 and the base material 12 and/or the article 10 may be combined in acontainer in an air-tight apparatus and a vacuum of 20 mm Hg to 80 mm Hgmay be applied for about 1 minute to 10 hours. Pressure treatment of 1psi to 40 psi may be applied for about 1 minute to about 10 hours andthe time and amount of vacuum or pressure treatment may vary and dependupon the amount of volatile composition 24 to be loaded in the basematerial 12 and/or the article 10, the type of base material 12 used,the intended use of the article 10, and other characteristics of thearticle 10.

In certain embodiments, the base material 12 and/or the article 10 maybe pre-treated with colorants, followed by treatment with the modulatingcoating 14. Colorants may include natural and synthetic dyes,water-resistant dyes, oil-resistant dyes, and combinations of water- andoil-resistant dyes. Colorants may be selected based on the compositionof the base material 12, and is well within the skill of those in theart. Suitable water-resistant colorants include oil soluble colorantsand wax soluble colorants. Examples of oil soluble colorants includePylakrome Dark Green and Pylakrome Red (Pylam Products Company, TempeAriz.). Suitable oil-resistant colorants include water solublecolorants. Examples of water soluble colorants include FD&C Blue No. 1and Carmine (Sensient, St. Louis, Mo.). A Lake type dye may also beused. Examples of Lake dyes are Cartasol Blue KRL-NA LIQ and CartasolYellow KGL LIQ (Clariant Corporation, Charlotte, N.C.). Pigments mayalso be used in coloring the base material 12 and may be added during orafter the manufacture of the base material 12. Such coloring or dyingmethods are known to those skilled in the art, and any suitable dyes,pigments, or colorants are contemplated by the present invention.Colorants may be used to affect the overall surface charge of the silicaor other hygroscopic substance 28 to enhance the interaction with thecoating.

EXAMPLES Example 1. Method for Making Modulating Coating 14 TreatmentSuspension

Modulating coating 14 with maltodextrin/silica ratio 50:50 at 30% totalsolids concentration was made by dissolving maltrodextrin solids in asilica suspension. A pre-weighed (15 kg) silica suspension (Snowtex®-Ofrom Nissan Chemical America Corporation; Houston, Tex.) was transferredto a large mixing container. Snowtex®-O contains silica nanoparticles at20% wt/wt solids in water. Water (2 kg) was added to the silicasuspension to ensure the final total solids concentration was 30%.Maltodextrin (3 kg) (Maltrin QD M500 from Grain Processing Corporation;Muscatine, Iowa) was added slowly to the stirring suspension of silica.The treatment suspension of modulating coating 14 was allowed to stiruntil all of the solid maltodextrin dissolved.

Example 2. Application of Modulating Coating 14 onto Outer Layer BaseMaterial 12

A treatment suspension of modulating coating 14 was made as described inExample 1. The base material 12 in this example was a paper rod withdimensions 13.97 cm (length) and 0.64 cm (diameter); the paper materialis A50 offset book paper (Glatfelter, York, Pa.). The mass of basematerial 12 was recorded before the base material 12 was dipped into thetreatment suspension. Base material 12 was submerged in the treatmentsuspension for 5 seconds. The base material 12 was removed from thetreatment suspension and allowed to air dry overnight. The mass of thebase material 12 coated with modulating coating 14 was recorded, and theamount of modulating coating 14 deposited onto the base material 12 wascalculated by subtracting the post-treatment mass from the pre-treatmentmass. As the results summarized in Table 1 below illustrate, the averageadd-on level of modulating coating 14 onto base material 12 is 1.9% whenthe application method is dipping of the dry base material 12.

TABLE 1 Sample Pre-mass (g) Post-mass (g) Add-on (g) Add-on (%) 1 2.8672.920 0.053 1.8 2 2.841 2.897 0.056 2.0 3 2.869 2.922 0.053 1.8 4 2.8682.925 0.057 2.0 5 2.875 2.934 0.059 2.1 6 2.875 2.924 0.049 1.7 7 2.8182.874 0.056 2.0 8 2.900 2.956 0.056 1.9 9 2.817 2.867 0.050 1.8 10 2.8722.934 0.062 2.2 Average 2.860 2.915 0.055 1.9

Example 3. Application of Modulating Coating 14 into Several Layers ofBase Material 12

A treatment suspension of modulating coating 14 was made as described inExample 1 with the following change: the water (2 kg) was replaced withmethanol (2 kg). The base material 12 in this example was a paper rodwith dimensions 13.97 cm (length) and 0.64 cm (diameter); the papermaterial is A50 offset book paper (Glatfelter; York, Pa.). The change insurface tension of the treatment suspension with methanol allowed forbetter penetration of the treatment suspension into the base material12. The mass of base material 12 was recorded before dipping into thetreatment suspension. This method allowed for a higher add-on load. Basematerial 12 was submerged in the treatment suspension for 5 seconds; thesubmerge time may range between 1 second to 30 seconds. The basematerial 12 was removed from the treatment suspension and allowed to airdry overnight. The mass of the base material 12 coated with modulatingcoating 14 was recorded, and the amount of modulating coating 14deposited onto the base material 12 was calculated by subtracting thepost-treatment mass from the pre-treatment mass. As the resultssummarized in Table 2 below illustrate, the average add-on level ofmodulating coating 14 onto base material 12 is 3.7% when the treatmentsuspension contains methanol.

TABLE 2 Sample (n = 3) Pre-mass (g) Post-mass (g) Add-on (g) Add-on (%)Average 2.856 2.961 0.105 3.7

Example 4. Application of Modulating Coating 14 by Vacuum-DrivenInfusion for Higher Load Level

A treatment suspension of modulating coating 14 was made as described inExample 1 and transferred to a container. The mass of base material 12was recorded. The base material 12 was then submerged in the treatmentsuspension and placed under vacuum (25 mm Hg) for 5 minutes. The vacuumwas removed, and the base material 12 was removed from the treatmentsuspension. The base material 12 treated with modulating coating 14 wasplaced under vacuum (25 mm Hg) for 1 minute to dry. Post-treatment masswas recorded, and the modulating coating 14 load level was calculated bysubtracting the pre-mass from the post-mass. As the results summarizedin Table 3 below illustrate, the average add-on level of modulatingcoating 14 onto base material 12 is 17.1% when the treatment suspensionwas infused via vacuum.

TABLE 3 Sample Pre-mass (g) Post-mass (g) Add-on (g) Add-on (%) 1 2.8833.379 0.496 17.2 2 2.872 3.361 0.489 17.0 3 2.890 3.380 0.490 17.0Average 2.882 3.373 0.492 17.1

Example 5. Weight-Loss Study 1

Base material 12 was loaded with fragrance Agilex 5224738 (AgilexFlavors & Fragrances; Piscataway, N.J.). The fragrance loaded testsamples were allowed to sit at ambient conditions (temp. 21° C.-27° C.;relative humidity 40%-60%), and the mass of each was recorded atspecified times. FIG. 5 is a graph showing the release rate in grams perday of the volatile composition, and FIG. 6 is a graph showing thecumulative amount of volatile composition released over time.

Example 6. Weight-Loss Study 2

Base material 12 treated with modulating coating 14 exhibits a steadyrelease of fragrance over time. Base material 12 treated with modulatingcoating 14, as described in Example 2, was loaded with fragrance Agilex5224738 (Agilex Flavors & Fragrances; Piscataway, N.J.). A second set ofsamples of base material 12 treated with modulating coating 14 withmaltodextrin/silica ratio 38:62 was loaded with fragrance Agilex5224738. Base material 12 without modulating coating 14 was loaded withthe same fragrance Agilex 5224738. The fragrance loaded test sampleswere allowed to sit at ambient conditions (temp. 21° C.-27° C.; relativehumidity 40%-60%), and the mass of each was recorded at specified times.FIG. 7 is a graph showing the release rate in grams per day of thevolatile composition from each sample, and FIG. 8 is a graph showing thecumulative amount of volatile composition released over time from eachsample.

Example 7. Weight-Loss Study 3

FIG. 9 is a graph showing base material 12 treated with modulatingcoating 14 and loaded with a smaller amount of a fragrance compositionhaving a higher concentration of volatile compounds provided a steadyrelease of fragrance over time. Likewise, base material 12 treated withmodulating coating 14 and loaded with a larger amount of a fragrancecomposition having a lower concentration of volatile compounds provideda substantially similar steady release of fragrance over time.

Sample A, base material 12 treated with modulating coating 14, asdescribed in Example 2, was loaded with fragrance Arylessence AH179443(Arylessence, Inc.; Marietta, Ga.). Sample B, base material 12 treatedwith modulating coating 14, was loaded with a lower concentration offragrance Arylessence AH179443 (labeled “Arylessence LC”). Samples C andD, two sets of base material 12 without modulating coating 14 wereloaded with the same two fragrances, respectively. The fragrance loadedtest samples were allowed to sit at ambient conditions (temp. 21° C.-27°C.; relative humidity 40%-60%), and the mass of each was recorded atspecified times. FIG. 9 is a graph showing the release rate in grams perday of the volatile composition from each sample, and FIG. 10 is a graphshowing the cumulative amount of volatile composition released over timefrom each sample. As illustrated in Table 4, the amount of fragranceloaded onto base material 12 is affected when the modulating coating 14is applied. (n=3)

TABLE 4 Pre- Post- Amount mass mass Load Sample Sample Description (g)(g) (g) B Maltrodextrin/silica, 50:50 @ 30% 3.63 5.03 1.40 solids,Arylessence LC D Control, untreated, Arylessence LC 3.54 5.94 2.40 AMaltrodextrin/silica, 50:50 @30% 3.63 5.10 1.47 solids, ArylessenceAH5224438 C Control, untreated, Arylessence 3.54 5.75 2.21 AH5224438

Example 8. Weight-Loss Study 4

Modulating coating 14 allows for more fragrance release in the latterhalf of the material use-cycle. Base material 12 treated with modulatingcoating 14 exhibits a steady release of fragrance over time. Basematerial 12 treated with modulating coating 14 was loaded with fragranceTakasago RY-007259 (Takasago International Corporation; Rockleigh,N.J.). Base material 12 without modulating coating 14 was loaded withthe same fragrance Takasago RY-007259. The fragrance loaded test sampleswere allowed to sit at ambient conditions (temp. 21° C.-27° C.; relativehumidity 40%-60%), and the mass of each was recorded at specified times.FIG. 11 is a graph showing the release rate in grams per day of thevolatile composition from each sample, and FIG. 12 is a graph showingthe cumulative amount of volatile composition released over time fromeach sample.

Different arrangements of the components depicted in the drawings ordescribed above, as well as components and steps not shown or describedare possible. Similarly, some features and sub-combinations are usefuland may be employed without reference to other features andsub-combinations. Embodiments of the invention have been described forillustrative and not restrictive purposes, and alternative embodimentswill become apparent to readers of this patent. Accordingly, the presentinvention is not limited to the embodiments described above or depictedin the drawings, and various embodiments and modifications may be madewithout departing from the scope of the claims below.

1-23. (canceled)
 24. A method of manufacturing a fragrance-releasingarticle, the article comprising a base material having fibers and pores,the method comprising: applying a volatile composition to the basematerial; applying a modulating coating to at least one outer surface ofthe base material, the modulating coating comprising a hygroscopicsubstance and a barrier substance dispersed therein; subjecting thecombination of the base material, the modulating coating, and thevolatile composition to a pressure that is different from atmosphericpressure.
 25. The method of claim 24, wherein the barrier substancecomprises a member selected from a group consisting of maltodextrins,dextrins, polysaccharides, carbohydrates, natural unmodified starches,modified starches, and combinations thereof.
 26. The method of claim 24,wherein the volatile composition comprises a member selected from thegroup consisting of fragrances, flavor compounds, odor-eliminatingcompounds, aromatherapy compounds, natural oils, essential oils,water-based scents, odor neutralizing compounds, and combinationsthereof.
 27. The method of claim 24, wherein the barrier substance isgrouped around particles of the hygroscopic substance throughelectrostatic interactions in the modulating coating due to a surfacecharge of the hygroscopic particles.
 28. The method of claim 24, whereinthe hygroscopic substance comprises particles with a diameter rangingfrom 1 nm to 100 nm.
 29. The method of claim 24, wherein the barriersubstance hinders a release of the volatile composition through themodulating coating; and wherein the hygroscopic substance facilitatesthe release of the volatile composition through the modulating coatingdue to presence of particles of the hygroscopic substance.
 30. Themethod of claim 24, wherein subjecting the combination of the basematerial, the modulating coating, and the volatile composition to apressure that is different from atmospheric pressure comprisessubjecting the combination of the base material, the modulating coating,and the volatile composition to a pressure that is less than atmosphericpressure.
 31. The method of claim 30, wherein the pressure is in a rangefrom 0.001 mm Hg to 700 mm Hg.
 32. The method of claim 24, whereinsubjecting the combination of the base material, the modulating coating,and the volatile composition to a pressure that is different fromatmospheric pressure comprises subjecting the combination of the basematerial, the modulating coating, and the volatile composition to apressure that is greater than atmospheric pressure.
 33. The method ofclaim 32, wherein the pressure is in a range from 1 psi to 40 psi. 34.The method of claim 24, wherein the pressure is applied for a period ofup to 1 hour and the pressure is variable during the period.
 35. Themethod of claim 24, wherein subjecting the combination of the basematerial, the modulating coating, and the volatile composition to apressure that is different from atmospheric pressure comprisessubjecting the combination of the base material, the modulating coating,and the volatile composition to a pressure that is less than atmosphericpressure, followed by a pressure that is greater than atmosphericpressure.
 36. The method of claim 24, wherein the fragrance-releasingarticle exhibits a ratio of a first day weight-loss value to a last dayweight-loss value in a range of 1 to 20 over a 30 day life cycle of thefragrance-releasing article.
 37. The method of claim 24, wherein thehygroscopic substance comprises silica nanoparticles.
 38. The method ofclaim 24, wherein particles of the hygroscopic substance attract watermolecules from a surrounding atmosphere into the modulating coating todisplace the volatile composition trapped by the barrier substancewithin the modulating coating.
 39. The method of claim 28, wherein thebarrier substance comprises maltodextrin.
 40. The method of claim 39,wherein a weight ratio of the maltodextrin to the hygroscopic substanceranges from 99:1 to 1:99.
 41. The method of claim 39, wherein a weightratio of the maltodextrin to the hygroscopic substance ranges from 25:75to 75:25.
 42. The method of claim 39, wherein a weight ratio of themaltodextrin to the hygroscopic substance is approximately 50:50. 43.The method of claim 24, wherein at least some of the volatilecomposition is located within the modulating coating, wherein themodulating coating further comprises water that is absorbed or adsorbedto the hygroscopic substance.
 44. A method of manufacturing afragrance-releasing article, the article comprising a rod-shapedstructural component comprising a base material wound around a verticalaxis, the base material having fibers and pores, the method comprising:applying a volatile composition to the base material; applying amodulating coating to at least one outer surface of the base material,the modulating coating comprising a hygroscopic substance and a barriersubstance dispersed therein; subjecting the combination of the basematerial, the modulating coating, and the volatile composition to apressure that is different from atmospheric pressure.